Pole-changer.



No. 890,840. PATENTED JUNE 16, 1908..

W. E. BUTLER & M. L. LANE.

POLE CHANGER.

P r T N FILED u. A PL 0A I0 I 1908 2 SHEETSSHEET 1.

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I I fltbo'umuao PATENTED JUNE 16, 1908.

W. E. BUTLER & M. L. LANE.

POLE CHANGER.

T H D M B. 1 APPLIGA ION LE A 1 1908 2 SHEETS SHBET 2' i 27 21 a2 55 g 3/ Z ZZZZZWZZJZZZ/Qf W /wywzllmw W 3% I r f Scrum UNITED sTATEs PATENT OFFICE.

WILLIAM E. BUTLER AND MORGAN L. LANE, OF OMAHA, NEBRASKA.

POLE-CHANGER.

Specification of Letters Patent.

Patented June 16, 1908.

Application filed March 11, 1908. Serial No. 420,463.

To all whom it may concern:

Be it known that we, WILLIAM E. BUTLER and M.ORGAN L. LANE, citizens of the United States, residing at Omaha, in the county of Douglas, State of Nebraska, have invented a new and useful Pole-Changer, of which the following is a specification.

This invention has reference to improvements in pole changers designed more articularly for use in telephone systems w ere it is desired to selectively operate two or more telephone signal bells upon the same line. This is done by impressing upon the line from a direct current source a succession of positive pulsations, a succession of negative pu sations, and an alternating current, with means for causing any one of these three t pes of current to be impressed upon the line at any one time. The signal receiving devices are, of course, properly constructed to respond to any predetermined one of the types of current and to no others, so that no matter what number of signal devices there may be upon the single line, within the limits of the number of ossible types of current, only the one signa device responsive to the particular type of current impressed will ring.

The present invention com rises a member made up of three conducting blocks or plates arranged in longitudinal series and insulated one from the other with one of the end plates lap ing but insulated from the intermediate p ate and brought into close relation but still insulated from the other end plate. In conjunction with these several plates are three brushes adapted to make contact with but two of the plates at any one time, but always includin the central plate except i or the exceedingly rief period of time when the brushes rest upon the insulating material, the latter being made 'ust wide enough to eliminate danger of s ort circuit as a brush passes from one block to another. The construction is such that the impulses, both positive and negative, are uniform and succeed each other regularly, and. are of the same duration and strength, thus producing an even lively ring of the bell affected.

The invention will be best understood by reference to the following detail description,

. taken in connection with the accompanying drawings, in which drawings,

Figure 1 is a diagram of the pole changing device in its normal osition, or position of rest, at which point t e negative impulse is bein sent to line. Fig. 2 is a diagram showing t ie other phase of operationof the device, {hat is, when a positive impulse is going to Referring to the drawings, there is shown a commutator 1 made up of three conducting blocks 2, 3 and 4 separated by insulating material 5. The block 3 is of less width than either of the blocks 2 or 4, while the block 4 has an extension 6 lying alongside of the block 3 and ap roaching the block 2 as closely as does t e block 3, but separated from the said block 3 by insulating material. On one side of the commutator 1 there are two spaced brushes 7, 8, and on the other side of the commutator in line with the brush 7 is still another brush 9.

In the drawings, there is shown a simple, but effective, means of imparting longitudinal movement in both directions to the commutator 1, but this means is not to be taken as the only means which may be used for the purpose, since any means which will impart to the commutator 1 a to and fro longitudinal movement may be used.

In the specific form shown in the drawings, the commutator is mounted u on a rod 10 about midway of the length of tile latter, and this rod has bearings 11 in a suitable frame 12, in which bearings the rod is capable of sliding. 1f the rod is round, then it may be kept from turning by a suitable spline, or the rod may be otherwise shaped t an round, and the bearings be made to conform to that shape and thus keep the rod from turning. Between the bearings 11, the rod is surrounded by short springs 13 constituting elastic buffers for the commutator at the limits of its travel in either direction. Beyond one of the bearings 11, the rod is surrounded by a spring 14 confined between the bearing and a head 15 formed on the rod. Beyond the other bearing 11, the rod carries an armature 16 in operative relation to an electro-mag'net 17 which may be of the ordinary horseshoe tylpe. One side of the magnet 17 is connecte by a conductor 18 to the block 4: of the commutator. The other side of the magnet 17 is connected by a conductor 19 to one side of a battery 20 through the switch 21, and the battery is connected by a conductor 22 to another conductor 23 leading to the brush 9. Now, when the switch 21 is closed, the circuit is completed through the conductor 19 to the magnets 17, thence by conductor 18 to the block 4, then by way of the brush 9 and conductor 23 to the conductor 22 and back to the battery. The magnet 17 is thereby energized and attracts the armature l6 and moves the commutator 1 against the action of the spring 14. The impulse thus given to the commutator moves it longitudinally until the brush 9 passes to the block 2, when the circuit to the battery 20 being broken, the magnet 17 becomes deenergized and the spring 14 then moves the commutator 1 back to its original position. This again causes the magnet 17 to be energized, and the commutator is again drawn so that the brush 9 is once more brought in contact with the block 2, a ain breaking the circuit of the battery 20. This is repeated so long as the switch 21 remains closed. 011 the opening of the switch 21, the commutator resumes 1ts initial position witluthe blocks 3 and 4 in contact with the brushes 7, S and 9, as shown in Fig. 1.

The main ringing battery is shown at 24, but, of course, any other suitable source of constant current may be used, and the showing of the battery 24 is to be taken as a conventional illustration of any constant current source. The positive side of the battery 24 is connected by a conductor 25 to the brush 7, and by another conductor 26 to a ringing key 27 ,the showing of which is conventional and is illustrative of any kind of circuit making and breaking device adapted for the purpose. This key, 27, is connected b a conductor 28 to the switch board to be ultimately connected up to the desired line in the usual manner, but, as the switch board and line connections form no part of the present invention, and since the signal receiving means may be of the usual selective type responsive to the different ty es of current, it is not deemed necessary to s ow any of these devices, or the circuit connections, in the drawings.

The negative side of battery 24 is connected by a conductor 29 to the brush 8, and by another conductor 30 to the negative key 31 which, in turn, is connected by a conductor 32 to the switch board. The conductor 23 connected to the brush 9 and also to the conductor 22 is continued to the alternating key 33, which latter is connected by a conductor 34 to the switch board. The block 3 is connected by a conductor 35 to ground, indicated at 36, or it may be grounded through the frame of the apparatus, or in any other manner.

Now let it be assumed that the a aratus is in the position shown in Fig. 1, and et it be assumed that the key 31 is depressed, current Will then flow from the positive side of the battery 24 through the conductor 25, to the brush 7, and thence to the block 3 and to ground through the conductor 35, thence returning through the conductor 32 and key 31 to the conductor 30 and back to the negative side of the battery 24. This is under the assumption that at the signal receiving mechanisms one side thereof is grounded. If under the same conditions of the commutator, the alternating key 33 was closed instead of the negative key 31, then the current would go to ground as before, and the negative current would return from the key 33 through the conductor 23 to the brush 9, thence by wa of the block 4 to the brush 8 and through t 10 conductor 29 to the negative side of the battery. Now, let it be assumed that the magnet 17 is energized and the con1 mutator l is moved to the position shown in Fig. 2. Under these conditions, the positive side of the battery is connected up by the conductor 26 to the positive kc 27, and, assuming that this key is closed, t 10 positive current impulse would flow to the corresponding signal apparatus and be there grounded, returning through the conductor 35 to the block 3 and by way of brush 8 and conductor 29 to the negative side of the battery. Suppose that under the last-named conditions regarding the commutator that the key 33 is closed instead of the key 27, then the positive im )ulse will flow by way of con ductor 25 to the brush 7 through the block 2 to the brush 9 and by way of the conductor 23 through the key 33 to the respective signal apparatus, returning as before through the conductor 35 and block 3, brush 8 and conductor 29 to the negative side of the battery. Thus it will be seen that in the position of the parts shown in Fig. 1, negative impulses may e established upon the lines 32 and 3 1, while in the position of the parts shown in Fig. 2, positive impulses may be established upon the lines 28 and 3 1. When the magnet 1.7 is alternately energized and de-magnetized by the action of the commutator 1 upon the circuit of the battery 20, then the conditions are such that if the negative key 31 is closed, there are thrown upon the line a succession of negative impulses separated by dead spaces of substantially the same time length as the impulses, and the succeeding impulses are of equal length and uniform current strength. When the positive key 27 is closed, then there are thrown upon the line positive impulses of even length and uniform current strength separated by like dead s aces. When the alternating key 33 is c osed, then there is thrown upon the line a succession of alternately negative and positive impulses of equal length and current strength and succeeding each other with practically no dead spaces between them.

hus current conditions are produced that cause a crisp, clear, ringing of the call bells at the receiving stations. Furthermore, the circuit is always grounded after each impulse and therefore all condensers in the circuit are discharged.

The switch 21 is only indicative of the escent, except when a transmitting key is closed to energize the ringing circuit.

\Ve claim:

1. A means for transmittin to the ringing circuits of telephone lines di erent types of current impulses from a constant current source, comprisin circuits individually and positively couple to the respective sides of the current source, and means for cou ling either the positive or ne ative side 0 the current source to the sai other circuit and the respective other side of the current source to ound.

2. A po e changer for transmittin to the ringing circuits of tele hone lines ifierent types of current impu ses from a constant current source comprising three contact plates one of which is connected to ground, contact brushes connected to the opposite poles of the constant current source, each rush being adapted to make contact with the ground plate and with a respective one of the other plates, circuit connections from each end of the current source to a respective line circuit, and circuit making and breaking means in each of said connections.

3. A pole changer for transmittin to the ringing circuits of tele hone lines iiierent types of current impu ses from a constant current source comprising a commutator having three contact plates insulated one from the other with one of the end plates overlapping the intermediate plate and approaching the other end plate as closely as does the intermediate plate, two spaced brushes arranged to engage each Intermediate plate, and a respective one of the end plates when the commutator is moved longitudinally, a constant current source connected at each end to a respective end of the current source, circuit connections leading from the current source, circuit making and reaking means for each of said connections, and means for moving the commutator to and fro under the brushes.

4. A pole changer for transmitting to the ringing surface of tele hone lines different types of current impu ses from a constant current source comprising a commutator having three contact plates insulated one from the other with one of the end plates overlapping the intermediate'plate and approaching the other end plate as closely as does the intermedia e plate, a brush ada ted to make contact with the interme iate plate and with a respective one of the end plates and connected to one side of the constant current source, another brush adapted to make contact with the intermediate plate and the respective other one of the end plates and connected to the other side of the constant current source, a third brush adapted to make contact with either of the end plates, and means for coupling up the brushes independently into respective circuits.

5. A means for independently transmitting to the ringing circuits of telephone lines, positive, negative and alternatmg current impulses from a single constant current source, comprising a commutator com osed of three conductlng blocks insulate one from the other with the end blocks in as close relation to each other as the intermediate block, a ground connection from the intermediate block, means for imparting a to and fro longitudinal movement to the commutator, two spaced brushes arranged to make contact with the intermediate block and the res ective one of the end blocks under the di erent movements of the commutator, circuit connections between the said two brushes and the respective ends of a constant current source and also to line, circuit making and breaking devices in the connections to line, another brush adapted to make contact with the end blocks in accordance with the position of the commutator, a circuit connection from the lastnamed brush to the line, and a circuit making and breaking device in the last-named connection.

6. A means for transmitting to the ringing circuits of telephone lines diiierent types of current impulses from a source of constant current, comprising a circuit positively coupled to the positive side of the current source, another circuit positively coupled to the negative side of the current source, a third circuit, and means for coupling the latter to the two poles of the current source in alternation.

7. A means for transmitting to the ringing circuits of telephone lines different types of current impulses from a source of constant current, comprising a circuit positively coupled to the positive side of the current source, another circuit ositively coupled to the negative side of t e current source, a third circuit, means for coupling the latter to the two poles of the current source in alternation, and means for completing any one or more of the circuits at will.

In testimony that we claim the foregoing as our own, we have hereto ailixed our sign atures in the presence of two witnesses.

' WILLIAM E. BUTLER. MORGAN L. LANE. Witnesses:

CnAs. P. SOUTHARD, WM. I. MALONE. 

